Field
Embodiments of the present invention generally relate to the field of DC powered electrical devices. More particularly, embodiments of the present invention relate to automatic recognition and swapping of polarity for DC powered electronic devices/systems.
Description of the Related Art
Electronic devices are designed to operate at certain predefined voltage/power profiles, requiring constant input power supply. Any fluctuation or unwanted input supply can damage the electronic device or an attached load. To protect these electronic devices from such damage, different types of protection circuits such as over current protection circuits, over voltage protection circuit, under voltage protection circuit, among others are generally attached with such electronic devices/loads. In case of DC powered electronic devices, where power to the devices is provided by a battery or DC power source, power must typically be provided with a particular polarity.
DC powered electronic devices present an essential problem regarding correct polarity activation of electronic circuits. In some cases, it is possible that the required polarity is not indicated on the electronic device, or that the polarity marks on the power source are not visible properly. In such cases, it becomes difficult for an electrician or for any person to attach a right pole/terminal of the power source with the right terminal of the electronic device. If the DC powered electronic device is attached with terminals of opposite polarity, it can damage both the attached electric device and/or the power source.
Though the problem of polarity detection is applicable for all electronic devices, it is more serious in the field of telecommunication and network devices where the devices are polarity specific. Many times the power supply in the telecommunication/network devices comes from a long distance, and the poles/wires marks may not be proper or can be misleading. For example, in order to run a telecommunication device, a low power DC voltage can be supplied from a telephone exchange to a remotely located device, and it becomes difficult for a deployment person to decide the polarity of the terminals. Similarly for network equipment that requires 48V DC input and are polarity specific, power is supplied through two cables, one carrying +48V and the other −48V. To help prevent human errors, some devices also use labels such as “+/−”, “−48V/RTN” or other variations to specify the polarities, which in creates confusion and is troublesome to customers during on-site installation and maintenance.
Therefore, there is a need of a system and circuit that solves above-mentioned issues, and enables efficient/automatic detection and switching of polarization, if required, for a DC powered electronic device.